RobLL":7e97dsq1 said:
Would it make a difference in how long a bottom paint job would last if I went into Lake Union every several months?
Not really.
From the perspective of a guy who has had all his boats bottom painted, I don't see a downside of having bottom paint. For fiberglass boats, if done properly, it gives you another barrier (coat) to alleviate issues with blisters.
If your boat doesn't spend more than a couple weeks at a time in the water, it probably isn't necessary. Where we live (warm water, high salinity), the slime and the critters will adhere enough to make a performance difference in about 10 days; even with regular use of the boat.
A good bottom paint job doesn't mean you won't see some of the slime, barnacles, and "grass", but it does mean they won't stick. If you've ever had to clean the bottom of a boat that spent "a bit too much time" in the water without a bottom job, you will appreciate the difference.
Back to the "downside"... you have a boat with bottom paint that doesn't spend a lot of time in the water? OK. As long as it is paint that remains effective when pulled out of the water, and I would think that would be the smart choice on any trailerable boat. Will it be as "pretty" on the trailer as a boat with shiny gelcoat on the bottom? No. But a boat is at its best-looking when it is in the water... and bottom paint on a boat in the water is hardly seen.
We had a trimaran sailboat that we used to race. I had a boatyard spray on multiple coats of bottom paint (in a color that matched our canvas)... smooth as a baby's behind. And, the boat was just as fast as with no bottom paint. On the more typical orange-peel texture with rolled on bottom paint, if it is ablative, it doesn't take a long time to wear itself reasonably smooth. I noticed no difference in the performance of our 25 before and after bottom paint.
As far as the "once you do it, you will have to maintain it" camp... well, yeah, it's a boat - there will always be maintaining. I think it is a heck of a lot easier to keep up bottom paint than it is to try to keep a bare hull (that spends time in the water) clean.
I don't see bottom paint as a bad thing. When buying a boat, I feel bottom paint is a plus. It is a lot less expensive to add more bottom paint than to start from scratch.
With boats the size of the C-Dory range, you have options - like launching and retrieving whenever you want. But, if the boat is going to spend months at a time in the water (either at a dock or out cruising), I feel bottom paint is "value added."
Some of you know we trailered our C-Dory a bunch. Our trailer had bunk slicks, and we never had an issue with paint coming off the boat onto the slicks, or the boat being "stickier" when launching.
As some here know, we bought another boat last month. Not a C-Dory, not even an enclosed helm type boat (that I truly appreciate so much). A small pontoon that we just got back from being bottom painted. I also added bunk slicks to the trailer. The aluminum takes a different primer/barrier and finish paint, but this will still make it easier to clean, since ours will be at our dock here at the house when we're home. I'm a believer.
Jim